What is the most commercially feasible route into space?Is it tourism? Is it satellite launching? Is it servicing the ISS?

Whatever makes the most money. If we figure out a way to mine asteroids - then its asteroid mining. If there is a metal alloy found on Mars, someone will figure out how to go get it. If the profit is tempting enough - there are investors willing to get it.

Tourism isn't there yet. Servicing the ISS is a dying and finite thing. Sat launching is probably the best of these options.

sanman wrote:

Space is by nature a high-capital business. And while govt has capital, it also has bureaucracy, lethargy and groupthink.

Is some sort of public-private partnership possible, as a compromise?

Long-term, no. They have completely different goals. Any private company that enters into a partnership with government is swallowed up in government. It can never be the other way around.

sanman wrote:

Is it still possible for the govt to hold up the main tentpole, while the private partners hold up their smaller poles, or pull on other ropes?

You tell me, how's the US space industry doing? Disarray, goalless, leaderless, matched with insufficient funding and a corrupt good-old boys pork laden government bid system = the complete fail you see right now.

sanman wrote:

When will private launch service providers be able to stand on their own two feet? Or will they forever be unsteady, requiring bailouts and other handouts?

If the government realizes they need to and relaxes legislation/laws, and if there is a way to make legitimate, sustained money (see above) - then yes.

blimp to orbit gives the largest volume and mass, an internally colonizable habitat space, the most bang for your buck of anything we have in the real world right now.

Of course you need to go smack jpl sensesless and toss their electrical impulse engines and standard rockets that they intend to attach to that blimp into the garbage and fit the whole thing with actually feasible ramrockets, because their blimp to orbit idea runs solid into several absolute walls, not enough delta v to push into orbit or too much weight to carry for the thing to float off in the first place.

space tourism in the sense i think that you and others mean it is a pipe dream which isn't going to be a reality until the cost to orbit comes down considerably, and while it may be inspirational and fun as an idea to you most of the people in the world who understand these issues view the idea of space tourism about the same way we see sesame street. Our capacity to suspend disbelief isn't that strong.. but.. whatever keeps the kids entertained...